What does this grouping mean?
- Thread starter Tac-O
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Yep. Watched a friend as he put 5 rounds on target at 600. the first and third shots went high right, the 2nd, 4th and 5th went lower and left . 1 & 3 went in the same hole. the other 3 were a group about 1.5", but 2" away from the other.
I was going to suggest you weight sort your brass until you revealed the issue. You can burn an enormous amount of powder chasing cheek weld. If the gun doesn't snap into place like a lego block you can't focus on the other fundamentals.
doverpack12
Well-Known Member
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- Nov 21, 2012
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- 214
I've had luck closing that type of grouping by pushing it harder with more powder. That was a Remington 700
Bob Wright
Well-Known Member
A double or even triple grouping on my 270 Win was related to a bedding issue. My choice of stock for this rifle just gave me fits as this rifle shoots bug holes, then deteriorates until I re-bed, add pillars, relieve interferences.
It's a weak laminated stock that constantly changes. So, look for bedding issues and possibly switch scopes with one that has parallax adjustments. Fixed parallax scopes are annoying. All the other comments are valid too. Just start a list and eliminate.
It's a weak laminated stock that constantly changes. So, look for bedding issues and possibly switch scopes with one that has parallax adjustments. Fixed parallax scopes are annoying. All the other comments are valid too. Just start a list and eliminate.
I fought this same issue with a proven gun after I got progressive lens glasses and it came down to cheek weld and head placement - I had someone else shoot the gun to verify it wasn't the gun/load - ended up changing my glasses
kduffy
Member
Looks like time to break out the vet wrap and packing foam. Get your cheek weld right. Lay your head completely relaxed behind the scope, on target and close your eyes, after a brief nap ( 5 or so seconds), look again and see where you are. If not on target, change something in your cheek rest. More foam, or less until you are on target when you open your eyes.
Tensilon
Well-Known Member
"It's a 30 06 tikka t3x superlite stainless barrel synthetic stock. I used a Dremel to remove extra stock material around the forearm to give it extra float."
So this is a plastic stock then.... and you didn't say that it is bedded. The tikka tupperware stocks are weak in the forearm area and you removed more material from the stock. Is this correct? Most of these T3 tupperware...stocks are flexy in the forearm area from the factory and to build yourself a truly stable platform with an eye to consistency, they need to be stabilized in the forearm to get rid of any flex. I don't generally use plastic stocked rifles just for this reason however I did buy a Remmy sp varmint barreled 243 and was able to turn it into a tack driver by not only bedding and putting pillars in the action and first part of the barrel but by stabilizing the stock with Matchgrade Synthetic Stock Stabilizer. My best guess is that this is the area that is causing your troubles. Try twisting your stock forearm...if it moves this will more than likely confirm that you have this issue. You can find this stabilizer kit in the US... just do a search. Also, you can read about this exact issue regarding T3 stocks at ballisticstudies.com. That group in my proflle picture was shot with that Remmy rifle with the stock that I mentioned... and it will consistently lay down groups like this. Do try and flex the forearm on your rifle and let us know what fixes it for you. As other have said this sounds like a stock issue.
Best of luck,
Tens
So this is a plastic stock then.... and you didn't say that it is bedded. The tikka tupperware stocks are weak in the forearm area and you removed more material from the stock. Is this correct? Most of these T3 tupperware...stocks are flexy in the forearm area from the factory and to build yourself a truly stable platform with an eye to consistency, they need to be stabilized in the forearm to get rid of any flex. I don't generally use plastic stocked rifles just for this reason however I did buy a Remmy sp varmint barreled 243 and was able to turn it into a tack driver by not only bedding and putting pillars in the action and first part of the barrel but by stabilizing the stock with Matchgrade Synthetic Stock Stabilizer. My best guess is that this is the area that is causing your troubles. Try twisting your stock forearm...if it moves this will more than likely confirm that you have this issue. You can find this stabilizer kit in the US... just do a search. Also, you can read about this exact issue regarding T3 stocks at ballisticstudies.com. That group in my proflle picture was shot with that Remmy rifle with the stock that I mentioned... and it will consistently lay down groups like this. Do try and flex the forearm on your rifle and let us know what fixes it for you. As other have said this sounds like a stock issue.
Best of luck,
Tens
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As mentioned, this could be several things. What comes to mind is head/eye position and amount of scope shadow, paralax, shooter stability and fundamentals, possibly mirage, barrel contact/bedding/rifle issues, reloading practices, load development process.
I think you can systemically eliminate these and get it to shoot better.
Step 1- Make sure the barrel is free floated and bed your recoil lug. Take mechanical/harmonic variability due to the rifle out of the equation as much as possible.
Step 2- There were a couple groups in there that make it seem like they had some potential (at least based on group size, but that doesn't mean a lot without velocity data). That being said what I see in those groups is consistent inconsistency. There is a lot of horizontal in a bunch of them, which makes me think of 4 things- trigger control, heart beat oscillation, eye position/scope shadow/sight picture/paralax, rifle cant and mirage. If your heart beat is causing a back and forth oscillation and you can't break a shot at the same place that interjects tremendous variability. The easiest way to solve this is with a trigger pull of 1.5lbs or less. Next is just some simple technical things. Set yourself up directly behind the rifle, adjust your paralax, make sure you have the same sight picture with equal amount of scope "shadow" around the image, use a firm rear bag and good front re/bipod so it recoils straight time the rear, and make sure you're level. When shooting for tiny groups even at 100 scope cant can throw you off by 1/4-1/3". Finally, if the mirage is intense all bets are off. Even at 100 yards you dont know if your actually aiming at the same point because the image is literally moving due to light distortion.
Step 3- Make sure your reloading practices are precise. Same brass (don't mix brands), anneal your brass every firing, consistent neck tension, temp stable powders, accurate powder charges, adjust the head space on your brass for your chamber. if your using a beam scale or just a powder drop you can be off by as much as 0.4g in either direction. That takes you out of a lot of nodes.
Step 4- load development. Don't get hung up on what groups are at 100. What matters is POI at distance, and consistent POI at distance is related to consistent MV. You don't necessarily need a chronograph/Magnetospeed/labradar but they truly give insight into the quality of your reloading practices and where pressure velocity nodes are, and that can greatly expedite the process. I use a Magnetospeed to do my initial load development and then shoot loads at promising loads at 300+. The further the better if there's no wind. That will tell you both how well it holds together at distance (likely due to low ES/SD) and using a ballistics calculator will let you true your velocity based on your POI. If it shoots good at distance it'll likely shoot at 100 but the flip side to that often isn't necessarily true.
Do that and I bet any couplets disappear.
I think you can systemically eliminate these and get it to shoot better.
Step 1- Make sure the barrel is free floated and bed your recoil lug. Take mechanical/harmonic variability due to the rifle out of the equation as much as possible.
Step 2- There were a couple groups in there that make it seem like they had some potential (at least based on group size, but that doesn't mean a lot without velocity data). That being said what I see in those groups is consistent inconsistency. There is a lot of horizontal in a bunch of them, which makes me think of 4 things- trigger control, heart beat oscillation, eye position/scope shadow/sight picture/paralax, rifle cant and mirage. If your heart beat is causing a back and forth oscillation and you can't break a shot at the same place that interjects tremendous variability. The easiest way to solve this is with a trigger pull of 1.5lbs or less. Next is just some simple technical things. Set yourself up directly behind the rifle, adjust your paralax, make sure you have the same sight picture with equal amount of scope "shadow" around the image, use a firm rear bag and good front re/bipod so it recoils straight time the rear, and make sure you're level. When shooting for tiny groups even at 100 scope cant can throw you off by 1/4-1/3". Finally, if the mirage is intense all bets are off. Even at 100 yards you dont know if your actually aiming at the same point because the image is literally moving due to light distortion.
Step 3- Make sure your reloading practices are precise. Same brass (don't mix brands), anneal your brass every firing, consistent neck tension, temp stable powders, accurate powder charges, adjust the head space on your brass for your chamber. if your using a beam scale or just a powder drop you can be off by as much as 0.4g in either direction. That takes you out of a lot of nodes.
Step 4- load development. Don't get hung up on what groups are at 100. What matters is POI at distance, and consistent POI at distance is related to consistent MV. You don't necessarily need a chronograph/Magnetospeed/labradar but they truly give insight into the quality of your reloading practices and where pressure velocity nodes are, and that can greatly expedite the process. I use a Magnetospeed to do my initial load development and then shoot loads at promising loads at 300+. The further the better if there's no wind. That will tell you both how well it holds together at distance (likely due to low ES/SD) and using a ballistics calculator will let you true your velocity based on your POI. If it shoots good at distance it'll likely shoot at 100 but the flip side to that often isn't necessarily true.
Do that and I bet any couplets disappear.
The other thing is that it looks like by what is written on your targets that your going up by like 0.4-0.6gr per charge weight. Maybe I'm reading that wrong but IMO that's way to much. Some guys will go up by 0.3 or 0.5 but they are shooting a ladder at distance (typically 500+) not 100. I'd recommend using increments of 0.2gr. Once you are close you can shoot your tie breaker in 0.1gr increments on either side to see which is best.
Rflshootr
Well-Known Member
1st off, at 63 grains you are 1 grain over max load according to Hodgdon and 6 grains over Sierra's data with their bullet. The load is out of tune. Normally increasing the powder or seating the bullet deeper in the case would probably straighten it out, but in this case you're already pushing the pressure limit. BACK OFF the powder charge to start with and re-tune the entire load from the beginning!
